Adjustable mounting for dressing devices for grinding wheels



Aug. 28, 1934. BLOOD 1,971,848

ADJUSTABLE MOUNTING FOR DRESSING DEVICES FOR GRINDING WHEELS Filed Feb. 20, 1933 2 Sheets-Sheet l gwmntoz Harold. L..Blo0d 1934- H. L. BLOOD 1,971,848

ADJUSTABLE MOUNTING FOR DRESSING DEVICES FOR GRINDING WHEELS Filed Feb. 20', 1935 2 Sheets-Sheet 2 place.

Patented Aug. 28, I934 j UNITED ."s'TATEs PATENT OFFICE P1971348 ADJUSTABLE,MOUNTING FOR DRESSING DEVICES FOR GRINDING WHEELS Harold Li Blood, Worcester, Mass.,' assignor to The Hcald Machine Company, Worcester; 7 -Mass.,acorporationof Massachusetts 7 p Application February 2 0, 1933, Serial No. 657,492

' 5 Claims. [(01. 125-11) The presentinvention relates to dressin'gor truing devices for use particularly in connection with the truing of the surfaces of abrasivewheels in grinding machines. 1.

method of adjusting the diamond in the supporting structure is to move the plug,- whichispreferably suitably threaded for'this purpose, in or set screw which holds the diamond-firmly'in the wheel which reduces the latter unduly.

The patent to Guild and Grimshaw No.

1,655,903 provides a diamond mounting "which normally maintains the diamond out of the path of the wheel but which is adapted for oscillation to dispose the diamond in the path 'ofthe Wheelfor a dressing operation.- In this patent, the-adjustment of the dressing tool is procured by aneccentric whch is adapted to vary the position; of the diamond carrying member by shifting the center of oscillation of said member. The eccentrio is arranged to be shifted'angul'arlyinsmall wheel along the proper horizontal dia'meter of said wheel. It is accordingly the principal-fob:

ject of the'present invention to provide for adjustment of the position-oithe'dressingtool'to f ward or away from the: axisof the wheelby movement of said tool in aplane parallel to the axis of rotation of the grindng wheel;

According to the-present invention,'the dressing: tool is mountedin a carryingmember andthe latter is supported for movement in a plane parallel to the 'aXisof the grinding wheel by strips of resilientmaterial by whichsaid carryingmemher is s pported on the machine'and which'per-j mit said member to move in aplanarpath under the control of an adjustingmembercooperating therewith. f

Other and further objects and advantages of the invention will" appearfrom the following detailed description taken in connection withthe; I v p I construction showinthe wheelhead is mounted accompanying drawings in which:'

This method of adjustment-results in many cases in an advance of the diamond too far; toward the wheel causing excessive dressing of I to be ground may-be carried on the table 1, and

- Fig.1 is a front elevation of porating" the invention. 1

Fig. zis-a-planview of the machine of Fig. 1 showing the dressing tool in position thereon.

Fig. 3 is a fragmentary vertical section substantiallyalong theline 33 of Fig.2 showing the dressing tool and the adjustment therefor.

Fig.4 is a plan view ofthe structure of Fig. 3 with partsbroken away to show more clearly the structure by which the dressing tool is adjusted.

- Like reference characters refer to like parts inthe difierent figures.

' Referring first to Fig. L the invention is shown in connectionv with a grinding machine which provides the. usual reciprocatory carriage 1 provided in internal grinding machines. In such a machine either the grinding wheel or the work a machine incorthe reciprocations of ,the latter are utilized in either case to produce a traversing movement between'the grinding wheel and the workpiece. In the construction shown, the table 1 supports and carries a workhead 2-and the grinding wheel 3 for the grinding operation is carried on a spindle 4 journaled in a wheelhead 5 carried by a bridge 6 which spans the slideways provided on the base of the machine for the reciprocatory movements-of the table. The grinding wheel 3' is rotated at a high rate of speed by any suitable mechanism, not shown, and the workpiece,- which i's mounted in a workholder 7 journaled in the workheadis suitably rotated, but prefera ably ata'slower speed; a 1

The-reciprocatory movement of the table 1' which causes the rotatinggrinding wheel to make the required traverse over the rotating workpiece is imparted in any well-known manner,as by the use of thefluid'pressure actuating mecha-' nism disclosed in theI-Ieald and Guild Patent No. 1,582,468, granted April 27, 1926.- Such mechanism does notg of itself, form a part of the present invention. It is sufiicient to note for the'purposes of the present application that the actuating mechanism procures a reversal of'th'e table at each end ofthe normal working stroke,

with the grinding wheel locatedwithin the bore on a cross-slide, not shown, which is transversely movable on the bridge 6, and movement of said cross-slide is procured by rotation of a crossfeed screw 12 by any suitable mechanism such as that disclosed in the Guild Patent No. 1,682,672, granted August 28, 1923. The crossfeed mechanism is not a feature of the present invention and will not be further described.

During the progress of the grinding operation, the workpiece is withdrawn from engagement with the grinding wheel to permit a dressing operation to be procured on said' wheel-" The separation of the grinding wheel and-workpiece may be procured in response to the operation of the crossfeed mechanism as fully disclosed in the above cited Guild Patent No. 1,682,672 or under the control or" gage members as in the Conradson, et a1. Patent No. 1,534,302,- granted April 21,

It is sufficientto note for the purpose of 1925. this application that the separation of the grinding wheel and the workpiece is obtained by an extended movement of the table 1 to the. left,

during which movement a dressing operation is performed on the grinding wheel. of the extended movement, the table is automatically reversed and the workpiece-is returned to operative engagement with the grinding wheel. The grinding operation then continues under the control of suitable mechanism similar to that dis: closed either in theabove cited patent to Conradson, et a1. or in the patent to Guild, above cited.

Referring now to Fig. 3, -the diamond or dressing tool 13 is carried in the end of a plug 14 which is adjustably mountedin a bore 15 provided by an oscillatory diamond carrying member 16, said plug being secured against movementflwithin the bore 15 by a set screw 17. The oscillatory member 16 is pivotally mounted on a pin 19 for swinging movement from the inoperative position shown in full lines of Fig. 3 into the horizontal dot-dash line position of this figure, in which position, said tool is in line with the periphery of the grinding wheel for operative engagement therewith. This downward swinging movement into horizontal position is procured at the same time, and preferably by the same mechanism which procures the extended movement of the table. For the purposes of this invention, it will be sufficient to note that, when the extended.

movement of the table is initiated, fluid under pressure is admitted through a conduit 18 into' the lower end of a cylinder 20 in the member 21' which carries the pin 19 on which the member 16 is pivotally mounted. A piston 22 is slidably mounted in the cylinder 20 and is notched at its upper end for engagement with a pin 23 secured to the member 16. Fluid under pressure admitted beneath the piston 22 in the cylinder 2 0 urgesv the piston upwardly toprocure oscillation of the member 16 into the horizontal dot-dashline-position. The downward oscillatory movement of said member 16 is limited by an adjustable screw 24 carried by said member 16 and held in ad-C justed position by -13. locking nut 25; the lower.

end of said adjustable screw engages a fixed plug 26 securely fastened in a part of, the member 21.

It will be apparent that the dressing tool, which, as best shown in Figs. 1 and .2, is mounted i on and movable with the table 1, is thus brought into alinement with the 1 grinding wheel for engagement therewith as the table movestotheleft.

During the movement of the table to the right, to,

return the grinding wheel: and workpiece into .1 operative engagement, .a roll 27, Fig.1, mounted At the end on the carrying member 16 engages a cam 28 adjustably secured to the bridge 6 to procure positive elevation of the dressing tool into inoperative position to prevent engagement of said tool with the wheelhead. Prior to the elevation of the dressing tool, into inoperative position, the conduit 18 connected 'to an exhaust pipe line by a suitable valve mechaism, not shown, to allow fluid beneath the piston 22 to exhaust from the cylinder.

' The above described structure functions properly only when the workpieces to be ground are all of the same predetermined size.

When the size of the workpiece is changed, it is necessary to adjust the dressing tool in proportion to the change in size of the workpiece, and the present invention involves, as pointed out above, a structure by which the dressing tool may be adjusted in a plane parallel to the axis of rotation of the grinding wheel and toward or away from said wheel. .This adjustment of thedressing tool in a plane parallel to the axisof rotation of the grinding wheel causes said tool to engage the wheel along a horizontal diameter regardless of, the change in positionof said dressing tool. This accurate engagement between the dressing tool and grinding wheelalong a horizontal diameter becomes particularly necessary in the useyof' small diameter wheels as will be apparent.

According to the present invention, the dressing tool is arranged for adjustment toward or away fromthe grinding wheelin aplane parallelto riage. Referring now to Figs. 3 and 4, a bracket 30 is secured by bolts 31 to the table 1 and the. member is connected to said bracket for movement relative thereto by'a series of strips 32 of resilient material which extend longitudinally of the members 21 and 30 on the forward side thereof and form a laminated connection therebetween. A similar; series of strips 33 vof resilient material extend longitudinally of said members on the rear side thereof, and are secured to said members by bolts 34 corresponding to bolts 35 which hold the strips 32 on said members. Each series forms a laminated connection between the members 21 and 30 which provides for a movement ;of the member 21 transversely of the machine in a horizontal path, and the .two series of laminations: support the member 21 against any vertical movement, so; that the dressing tool isv always in thesame horizontal plane, when in, dressing position, regardlessof theposition'of the member 21.

V The. position of the member 21 relative to the bracket 30 ;is determined by an'eccentric disc 36 securedto a pin 37 journaled-in'a bearing 38 forming a part of the bracket 30, The eccentric: disc engages a friction plate 40 secured to the rearward side of the member 21 by one of the bolts 34, and oscillation-of the pin 37 will turn the disc 36 to procurea corresponding forward or rear-ward; movement of, the member 21. An arm 41 issecuredtothe end of the pin 37 opposite the eccentric disc and said arm extends in overlying relation to the bracket30 toward which it is urged by a spring 42 whichisconnected at opposite ends to the bracket 30 and. the arm 41 respectively. The outer end of said arm carries an adjusting screw 43 having an enlarged head 44, and the end of said-adjusting screw engages .a portion of the b f k tfifi- F m n .01 theh ed f t -s raises or lowers the arm el 'andthus procures a slight angular movement of the eccentric disc 36, thereby procuring a very minute forward or rearward movement of the member 21 on which, as above stated, the dressing tool is oscillatably mounted.

From the foregoing, it will be apparent that the present invention provides for a forward or rearward adjusting movement of the dressing tool for positioning the latter in the path of the grinding wheel, and the adjusting movement of said tool is along a planar path which is parallel to the axis of the grinding wheel. The adjustment provides for very minute adjustments of the dressing tool by reason of the construction above described, and said tool is accordingly accurately positioned relative to the axis of the dressing tool to procure a suitable dressing operation on said wheel.

I claim,

1. In apparatus of the class described, a dressing tool, a carrying member for said tool, a base or supporting member on which said member is mounted, and means for supporting said carrying member on the base, said means comprising a plurality of strips of resilient material secured to the carrier member and to the base in parallel relation, and forming the only connection between said base and the carrying member, movement of said carrying member being limited by said strips to a planar path substantially perpendicular to the plane of said strips.

2. In apparatus of the class described, a dressing tool, a carrying member for said tool, a base or supporting member on which said member is mounted, and means for supporting said carrymounted, means for supporting said carrying member on the base comprising spaced series of thin resilient strips forming laminations, said laminations being secured to, and forming the only connection between, said carrying member and the base, thereby causing said carrying member to move in a planar path, and means for adjusting said carrying member relative to the base in a plane substantially perpendicular to the plane of said strips. 7

4. In apparatus of the class described, a dressing tool, a carrying member for said tool, a base or supporting member on which said member is mounted, flexible connections forming the only supporting structure between said member and the base to cause said member to move in a planar path relative to said base, and an angularly adjustable eccentric disc for adjusting the position of the carrying member relative to the base in said planar path.

5. In apparatus of the class described, a dressing tool, a carrying member for said tool, a base or supporting member on which said member is mounted, flexible connections between said member and the base to cause said member to move in a planar path relative to said base, an angularly adjustable eccentric disc'for adjusting the relative position of the carrying member on the base, an arm movable with said disc, and means engaging said arm 'for adjusting the position of said arm and thus the angular position of the disc.

6. In apparatus of the class described, a dressing tool, a pivotally mounted member in which said tool is positioned, a carrying member on which said member is pivotally mounted, a supporting structure 'on which said carrying memher is mounted, means for supporting said carrying member on the supporting structure comprising spaced series of thin resilient strips forming laminations, the latter being secured to, and 110 forming the only connection between, said carrying member and the base, thereby causing said member to move in a planar path, and means for 

